Surgical instrument with variable clamping force

ABSTRACT

An ultrasonic instrument includes a body and a shaft assembly extending distally from the body. The shaft assembly includes an acoustic waveguide. The instrument further includes an end effector including an ultrasonic blade. The ultrasonic blade is in acoustic communication with the acoustic waveguide. The instrument further includes a sensor configured to sense at least one characteristic of the shaft assembly and/or the end effector. The end effector is configured to be activated at varying power levels based on the at least one characteristic sensed by the sensor.

BACKGROUND

A variety of surgical instruments include an end effector having a bladeelement that vibrates at ultrasonic frequencies to cut and/or sealtissue (e.g., by denaturing proteins in tissue cells). These instrumentsinclude one or more piezoelectric elements that convert electrical powerinto ultrasonic vibrations, which are communicated along an acousticwaveguide to the blade element. The precision of cutting and coagulationmay be controlled by the operator's technique and adjusting the powerlevel, blade edge angle, tissue traction, and blade pressure.

Examples of ultrasonic surgical instruments include the HARMONIC ACE®Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONICFOCUS® Ultrasonic Shears, and the HARMONIC SYNERGY® Ultrasonic Blades,all by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. Further examplesof such devices and related concepts are disclosed in U.S. Pat. No.5,322,055, entitled “Clamp Coagulator/Cutting System for UltrasonicSurgical Instruments,” issued Jun. 21, 1994, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 5,873,873, entitled“Ultrasonic Clamp Coagulator Apparatus Having Improved Clamp Mechanism,”issued Feb. 23, 1999, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 5,980,510, entitled “Ultrasonic ClampCoagulator Apparatus Having Improved Clamp Arm Pivot Mount,” issued Nov.9, 1999, the disclosure of which is incorporated by reference herein;U.S. Pat. No. 6,283,981, entitled “Method of Balancing AsymmetricUltrasonic Surgical Blades,” issued Sep. 4, 2001, the disclosure ofwhich is incorporated by reference herein; U.S. Pat. No. 6,309,400,entitled “Curved Ultrasonic Blade having a Trapezoidal Cross Section,”issued Oct. 30, 2001, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 6,325,811, entitled “Blades withFunctional Balance Asymmetries for use with Ultrasonic SurgicalInstruments,” issued Dec. 4, 2001, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 6,423,082, entitled“Ultrasonic Surgical Blade with Improved Cutting and CoagulationFeatures,” issued Jul. 23, 2002, the disclosure of which is incorporatedby reference herein; U.S. Pat. No. 6,773,444, entitled “Blades withFunctional Balance Asymmetries for Use with Ultrasonic SurgicalInstruments,” issued Aug. 10, 2004, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 6,783,524, entitled“Robotic Surgical Tool with Ultrasound Cauterizing and CuttingInstrument,” issued Aug. 31, 2004, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 8,057,498, entitled“Ultrasonic Surgical Instrument Blades,” issued Nov. 15, 2011, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.8,461,744, entitled “Rotating Transducer Mount for Ultrasonic SurgicalInstruments,” issued Jun. 11, 2013, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 8,591,536, entitled“Ultrasonic Surgical Instrument Blades,” issued Nov. 26, 2013, thedisclosure of which is incorporated by reference herein; and U.S. Pat.No. 8,623,027, entitled “Ergonomic Surgical Instruments,” issued Jan. 7,2014, the disclosure of which is incorporated by reference herein.

Still further examples of ultrasonic surgical instruments are disclosedin U.S. Pub. No. 2006/0079874, entitled “Tissue Pad for Use with anUltrasonic Surgical Instrument,” published Apr. 13, 2006, the disclosureof which is incorporated by reference herein; U.S. Pub. No.2007/0191713, entitled “Ultrasonic Device for Cutting and Coagulating,”published Aug. 16, 2007, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2007/0282333, entitled “UltrasonicWaveguide and Blade,” published Dec. 6, 2007, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2008/0200940, entitled“Ultrasonic Device for Cutting and Coagulating,” published Aug. 21,2008, the disclosure of which is incorporated by reference herein; U.S.Pub. No. 2008/0234710, entitled “Ultrasonic Surgical Instruments,”published Sep. 25, 2008, the disclosure of which is incorporated byreference herein; and U.S. Pub. No. 2010/0069940, entitled “UltrasonicDevice for Fingertip Control,” published Mar. 18, 2010, the disclosureof which is incorporated by reference herein.

Some ultrasonic surgical instruments may include a cordless transducersuch as that disclosed in U.S. Pub. No. 2012/0112687, entitled “RechargeSystem for Medical Devices,” published May 10, 2012, the disclosure ofwhich is incorporated by reference herein; U.S. Pub. No. 2012/0116265,entitled “Surgical Instrument with Charging Devices,” published May 10,2012, the disclosure of which is incorporated by reference herein;and/or U.S. Pat. App. No. 61/410,603, filed Nov. 5, 2010, entitled“Energy-Based Surgical Instruments,” the disclosure of which isincorporated by reference herein.

Additionally, some ultrasonic surgical instruments may include anarticulating shaft section. Examples of such ultrasonic surgicalinstruments are disclosed in U.S. Pub. No. 2014/0005701, published Jan.2, 2014, entitled “Surgical Instruments with Articulating Shafts,” thedisclosure of which is incorporated by reference herein; and U.S. Pub.No. 2014/0114334, published Apr. 24, 2014, entitled “Flexible HarmonicWaveguides/Blades for Surgical Instruments,” the disclosure of which isincorporated by reference herein.

While several surgical instruments and systems have been made and used,it is believed that no one prior to the inventors has made or used theinvention described in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim this technology, it is believed this technologywill be better understood from the following description of certainexamples taken in conjunction with the accompanying drawings, in whichlike reference numerals identify the same elements and in which:

FIG. 1 depicts a block schematic view of an exemplary surgical system;

FIG. 2 depicts a side elevational view of an exemplary form that aninstrument of the system of FIG. 1 may take;

FIG. 3 depicts a side elevational view of an exemplary alternative formthat an instrument of the system of FIG. 1 may take;

FIG. 4A depicts a cross-sectional view of the instrument of FIG. 3,taken along line 4-4 of FIG. 3, showing an end effector of theinstrument in a first partially closed clamping configuration;

FIG. 4B depicts a cross-sectional view of the instrument of FIG. 3,taken along line 4-4 of FIG. 3, showing the end effector in a secondpartially closed clamping configuration;

FIG. 4C depicts a cross-sectional view of the instrument of FIG. 3,taken along line 4-4 of FIG. 3, showing the end effector in a fullyclosed clamping configuration;

FIG. 5 depicts a cross-sectional view of the instrument of FIG. 3, takenalong line 5-5 of FIG. 3;

FIG. 6 depicts a side elevational view of an another exemplaryalternative form that an instrument of the system of FIG. 1 may take;

FIG. 7 depicts a schematic view of a first set of internal components ofthe instrument of FIG. 6;

FIG. 8 depicts a schematic view of a second set of internal componentsof the instrument of FIG. 6;

FIG. 9 depicts an exemplary spring compression mechanism that may beincorporated into the instrument of FIG. 6;

FIG. 10 depicts an exemplary alternative spring compression mechanismthat may be incorporated into the instrument of FIG. 6;

FIG. 11 depicts a side elevational view of an another exemplaryalternative form that an instrument of the system of FIG. 1 may take;and

FIG. 12 depicts a top elevational view of the instrument of FIG. 11.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the technology may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presenttechnology, and together with the description serve to explain theprinciples of the technology; it being understood, however, that thistechnology is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,embodiments, and advantages of the technology will become apparent tothose skilled in the art from the following description, which is by wayof illustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Thefollowing-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

For clarity of disclosure, the terms “proximal” and “distal” are definedherein relative to an operator or other operator grasping a surgicalinstrument having a distal surgical end effector. The term “proximal”refers to the position of an element closer to the operator or otheroperator and the term “distal” refers to the position of an elementcloser to the surgical end effector of the surgical instrument andfurther away from the operator or other operator.

I. Overview of Exemplary Ultrasonic Surgical System

FIG. 1 shows components of an exemplary surgical system (10) indiagrammatic block form. As shown, system (10) comprises an ultrasonicgenerator (12) and an ultrasonic surgical instrument (20). As will bedescribed in greater detail below, instrument (20) is operable to cuttissue and seal or weld tissue (e.g., a blood vessel, etc.)substantially simultaneously, using ultrasonic vibrational energy.Generator (12) and instrument (20) are coupled together via cable (14).Cable (14) may comprise a plurality of wires; and may provideunidirectional electrical communication from generator (12) toinstrument (20) and/or bidirectional electrical communication betweengenerator (12) and instrument (20). By way of example only, cable (14)may comprise a “hot” wire for electrical power to surgical instrument(20), a ground wire, and a signal wire for transmitting signals fromsurgical instrument (20) to ultrasonic generator (12), with a shieldsurrounding the three wires. In some versions, separate “hot” wires areused for separate activation voltages (e.g., one “hot” wire for a firstactivation voltage and another “hot” wire for a second activationvoltage, or a variable voltage between the wires proportional to thepower requested, etc.). Of course, any other suitable number orconfiguration of wires may be used. It should also be understood thatsome versions of system (10) may incorporate generator (12) intoinstrument (20), such that cable (14) may simply be omitted.

By way of example only, generator (12) may comprise the GEN04, GEN11, orGEN 300 sold by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. Inaddition or in the alternative, generator (12) may be constructed inaccordance with at least some of the teachings of U.S. Pub. No.2011/0087212, entitled “Surgical Generator for Ultrasonic andElectrosurgical Devices,” published Apr. 14, 2011, the disclosure ofwhich is incorporated by reference herein. Alternatively, any othersuitable generator (12) may be used. As will be described in greaterdetail below, generator (12) is operable to provide power to instrument(20) to perform ultrasonic surgical procedures.

Instrument (20) comprises a handpiece (22), which is configured to begrasped in one hand (or two hands) of an operator and manipulated by onehand (or two hands) of the operator during a surgical procedure. Forinstance, in some versions, handpiece (22) may be grasped like a pencilby the operator. In some other versions, handpiece (22) may include ascissor grip that may be grasped like scissors by the operator. In someother versions, handpiece (22) may include a pistol grip that may begrasped like a pistol by the operator. Of course, handpiece (22) may beconfigured to be gripped in any other suitable fashion. Furthermore,some versions of instrument (20) may substitute handpiece (22) with abody that is coupled to a robotic surgical system that is configured tooperate instrument (e.g., via remote control, etc.). In the presentexample, a blade (24) extends distally from the handpiece (22).Handpiece (22) includes an ultrasonic transducer (26) and an ultrasonicwaveguide (28), which couples ultrasonic transducer (26) with blade(24). Ultrasonic transducer (26) receives electrical power fromgenerator (12) via cable (14). By virtue of its piezoelectricproperties, ultrasonic transducer (26) is operable to convert suchelectrical power into ultrasonic vibrational energy.

Ultrasonic waveguide (28) may be flexible, semi-flexible, rigid, or haveany other suitable properties. As noted above, ultrasonic transducer(26) is integrally coupled with blade (24) via ultrasonic waveguide(28). In particular, when ultrasonic transducer (26) is activated tovibrate at ultrasonic frequencies, such vibrations are communicatedthrough ultrasonic waveguide (28) to blade (24), such that blade (24)will also vibrate at ultrasonic frequencies. When blade (24) is in anactivated state (i.e., vibrating ultrasonically), blade (24) is operableto effectively cut through tissue and seal tissue. Ultrasonic transducer(26), ultrasonic waveguide (28), and blade (24) together thus form anacoustic assembly providing ultrasonic energy for surgical procedureswhen powered by generator (12). Handpiece (22) is configured tosubstantially isolate the operator from the vibrations of the acousticassembly formed by transducer (26), ultrasonic waveguide (28), and blade(24).

In some versions, ultrasonic waveguide (28) may amplify the mechanicalvibrations transmitted through ultrasonic waveguide (28) to blade (24).Ultrasonic waveguide (28) may further have features to control the gainof the longitudinal vibration along ultrasonic waveguide (28) and/orfeatures to tune ultrasonic waveguide (28) to the resonant frequency ofsystem (10). For instance, ultrasonic waveguide (28) may have anysuitable cross-sectional dimensions/configurations, such as asubstantially uniform cross-section, be tapered at various sections, betapered along its entire length, or have any other suitableconfiguration. Ultrasonic waveguide (28) may, for example, have a lengthsubstantially equal to an integral number of one-half system wavelengths(nλ/2). Ultrasonic waveguide (28) and blade (24) may be fabricated froma solid core shaft constructed out of a material or combination ofmaterials that propagates ultrasonic energy efficiently, such astitanium alloy (i.e., Ti-6Al-4V), aluminum alloys, sapphire, stainlesssteel, or any other acoustically compatible material or combination ofmaterials.

In the present example, the distal end of blade (24) is located at aposition corresponding to an anti-node associated with resonantultrasonic vibrations communicated through waveguide (28) (i.e., at anacoustic anti-node), in order to tune the acoustic assembly to apreferred resonant frequency f_(o) when the acoustic assembly is notloaded by tissue. When transducer (26) is energized, the distal end ofblade (24) is configured to move longitudinally in the range of, forexample, approximately 10 to 500 microns peak-to-peak, and in someinstances in the range of about 20 to about 200 microns at apredetermined vibratory frequency f_(o) of, for example, 55.5 kHz. Whentransducer (26) of the present example is activated, these mechanicaloscillations are transmitted through waveguide (28) to reach blade (24),thereby providing oscillation of blade (24) at the resonant ultrasonicfrequency. Thus, the ultrasonic oscillation of blade (24) maysimultaneously sever the tissue and denature the proteins in adjacenttissue cells, thereby providing a coagulative effect with relativelylittle thermal spread. In some versions, an electrical current may alsobe provided through blade (24) to also cauterize the tissue.

By way of example only, ultrasonic waveguide (28) and blade (24) maycomprise components sold under product codes SNGHK and SNGCB by EthiconEndo-Surgery, Inc. of Cincinnati, Ohio. By way of further example only,ultrasonic waveguide (28) and/or blade (24) may be constructed andoperable in accordance with the teachings of U.S. Pat. No. 6,423,082,entitled “Ultrasonic Surgical Blade with Improved Cutting andCoagulation Features,” issued Jul. 23, 2002, the disclosure of which isincorporated by reference herein. As another merely illustrativeexample, ultrasonic waveguide (28) and/or blade (24) may be constructedand operable in accordance with the teachings of U.S. Pat. No.5,324,299, entitled “Ultrasonic Scalpel Blade and Methods ofApplication,” issued Jun. 28, 1994, the disclosure of which isincorporated by reference herein. Other suitable properties andconfigurations of ultrasonic waveguide (28) and blade (24) will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Handpiece (22) of the present example also includes a control selector(30) and an activation switch (32), which are each in communication witha circuit board (34). By way of example only, circuit board (34) maycomprise a conventional printed circuit board, a flex circuit, arigid-flex circuit, or may have any other suitable configuration.Control selector (30) and activation switch (32) may be in communicationwith circuit board (34) via one or more wires, traces formed in acircuit board or flex circuit, and/or in any other suitable fashion.Circuit board (34) is coupled with cable (14), which is in turn coupledwith control circuitry (16) within generator (12). Activation switch(32) is operable to selectively activate power to ultrasonic transducer(26). In particular, when switch (32) is activated, such activationprovides communication of appropriate power to ultrasonic transducer(26) via cable (14). By way of example only, activation switch (32) maybe constructed in accordance with any of the teachings of the variousreferences cited herein. Other various forms that activation switch (32)may take will be apparent to those of ordinary skill in the art in viewof the teachings herein.

In the present example, surgical system (10) is operable to provide atleast two different levels or types of ultrasonic energy (e.g.,different frequencies and/or amplitudes, etc.) at blade (24). To thatend, control selector (30) is operable to permit the operator to selecta desired level/amplitude of ultrasonic energy. By way of example only,control selector (30) may be constructed in accordance with any of theteachings of the various references cited herein. Other various formsthat control selector (30) may take will be apparent to those ofordinary skill in the art in view of the teachings herein. In someversions, when an operator makes a selection through control selector(30), the operator's selection is communicated back to control circuitry(16) of generator (12) via cable (14), and control circuitry (16)adjusts the power communicated from generator (12) accordingly the nexttime the operator actuates activation switch (32).

It should be understood that the level/amplitude of ultrasonic energyprovided at blade (24) may be a function of characteristics of theelectrical power communicated from generator (12) to instrument (20) viacable (14). Thus, control circuitry (16) of generator (12) may provideelectrical power (via cable (14)) having characteristics associated withthe ultrasonic energy level/amplitude or type selected through controlselector (30). Generator (12) may thus be operable to communicatedifferent types or degrees of electrical power to ultrasonic transducer(26), in accordance with selections made by the operator via controlselector (30). In particular, and by way of example only, generator (12)may increase the voltage and/or current of the applied signal toincrease the longitudinal amplitude of the acoustic assembly. As amerely illustrative example, generator (12) may provide selectabilitybetween a “level 1” and a “level 5,” which may correspond with a blade(24) vibrational resonance amplitude of approximately 50 microns andapproximately 90 microns, respectively. Various ways in which controlcircuitry (16) may be configured will be apparent to those of ordinaryskill in the art in view of the teachings herein. It should also beunderstood that control selector (30) and activation switch (32) may besubstituted with two or more activation switches (32). In some suchversions, one activation switch (32) is operable to activate blade (24)at one power level/type while another activation switch (32) is operableto activate blade (24) at another power level/type, etc.

In some alternative versions, control circuitry (16) is located withinhandpiece (22). For instance, in some such versions, generator (12) onlycommunicates one type of electrical power (e.g., just one voltage and/orcurrent available) to handpiece (22), and control circuitry (16) withinhandpiece (22) is operable to modify the electrical power (e.g., thevoltage of the electrical power), in accordance with selections made bythe operator via control selector (30), before the electrical powerreaches ultrasonic transducer (26). Furthermore, generator (12) may beincorporated into handpiece (22) along with all other components ofsurgical system (10). For instance, one or more batteries (not shown) orother portable sources of power may be provided in handpiece (22). Stillother suitable ways in which the components depicted in FIG. 1 may berearranged or otherwise configured or modified will be apparent to thoseof ordinary skill in the art in view of the teachings herein.

II. Overview of Exemplary Ultrasonic Surgical Instrument

The following discussion relates to various exemplary components andconfigurations for instrument (20). It should be understood that thevarious examples of instrument (20) described below may be readilyincorporated into a surgical system (10) as described above. It shouldalso be understood that the various components and operability ofinstrument (20) described above may be readily incorporated into theexemplary versions of instrument (110) described below. Various suitableways in which the above and below teachings may be combined will beapparent to those of ordinary skill in the art in view of the teachingsherein. It should also be understood that the below teachings may bereadily combined with the various teachings of the references that arecited herein.

FIG. 2 illustrates an exemplary ultrasonic surgical instrument (110). Atleast part of instrument (110) may be constructed and operable inaccordance with at least some of the teachings of U.S. Pat. Nos.5,322,055; 5,873,873; 5,980,510; 6,325,811; 6,773,444; 6,783,524;8,461,744; U.S. Pub. No. 2009/0105750; U.S. Pub. No. 2006/0079874; U.S.Pub. No. 2007/0191713; U.S. Pub. No. 2007/0282333; U.S. Pub. No.2008/0200940; U.S. Pub. No. 2010/0069940; U.S. Pub. No. 2012/0112687;U.S. Pub. No. 2012/0116265; U.S. Pub. No. 2014/0005701; U.S. Pat. Pub.No. 2014/0114334; U.S. patent application Ser. No. 14/028,717; and/orU.S. Pat. App. No. 61/410,603. The disclosures of each of the foregoingpatents, publications, and applications are incorporated by referenceherein. As described therein and as will be described in greater detailbelow, instrument (110) is operable to cut tissue and seal or weldtissue substantially simultaneously. It should also be understood thatinstrument (110) may have various structural and functional similaritieswith the HARMONIC ACE® Ultrasonic Shears, the HARMONIC WAVE® UltrasonicShears, the HARMONIC FOCUS® Ultrasonic Shears, and/or the HARMONICSYNERGY® Ultrasonic Blades. Furthermore, instrument (110) may havevarious structural and functional similarities with the devices taughtin any of the other references that are cited and incorporated byreference herein.

To the extent that there is some degree of overlap between the teachingsof the references cited herein, the HARMONIC ACE® Ultrasonic Shears, theHARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears,and/or the HARMONIC SYNERGY® Ultrasonic Blades, and the followingteachings relating to instrument (110), there is no intent for any ofthe description herein to be presumed as admitted prior art. Severalteachings herein will in fact go beyond the scope of the teachings ofthe references cited herein and the HARMONIC ACE® Ultrasonic Shears, theHARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears,and the HARMONIC SYNERGY® Ultrasonic Blades.

Instrument (110) of the present example comprises a handle assembly(120), a shaft assembly (130), and an end effector (140). Handleassembly (120) comprises a body (22) including a pistol grip (124) and apair of buttons (126). Handle assembly (120) also includes a trigger(128) that is pivotable toward and away from pistol grip (124). Itshould be understood, however, that various other suitableconfigurations may be used, including but not limited to a scissor gripconfiguration. End effector (140) includes an ultrasonic blade (160) anda pivoting clamp arm (144). Ultrasonic blade (160) may be configured andoperable just like ultrasonic blade (24) described above.

Clamp arm (144) is pivotably coupled with an inner tube and an outertube that form shaft assembly (130). Such an inner and outer tubeconfiguration may be provided in accordance with the teachings ofvarious references that are cited herein. Clamp arm (144) is furthercoupled with trigger (128). Trigger (128) is operable to drive one ofthe tubes of shaft assembly (130) longitudinally while the other tube ofshaft assembly (130) remains stationary. This relative longitudinalmovement between the tubes of shaft assembly (130) provides pivotalmovement of clamp arm (144). Clamp arm (144) is thus pivotable towardultrasonic blade (160) in response to pivoting of trigger (128) towardpistol grip (124); and clamp arm (144) is pivotable away from ultrasonicblade (160) in response to pivoting of trigger (128) away from pistolgrip (124). Clamp arm (144) is thereby operable to cooperate withultrasonic blade (160) to grasp and release tissue; and clamp arm (144)is further operable to compress tissue against ultrasonic blade (160) tothereby enhance the communication of ultrasonic vibration fromultrasonic blade (160) to the tissue. Various suitable ways in whichclamp arm (144) may be coupled with trigger (128) will be apparent tothose of ordinary skill in the art in view of the teachings herein. Insome versions, one or more resilient members are used to bias clamp arm(144) and/or trigger (128) to the open position shown in FIG. 2.

An ultrasonic transducer assembly (112) extends proximally from body(122) of handle assembly (120). Transducer assembly (112) may beconfigured and operable just like transducer (26) described above.Transducer assembly (112) is coupled with a generator (116) via a cable(114). It should be understood that transducer assembly (112) receiveselectrical power from generator (116) and converts that power intoultrasonic vibrations through piezoelectric principles. Generator (116)may be configured and operable like generator (12) described above.Generator (116) may thus include a power source and control module thatis configured to provide a power profile to transducer assembly (112)that is particularly suited for the generation of ultrasonic vibrationsthrough transducer assembly (112). It should also be understood that atleast some of the functionality of generator (116) may be integratedinto handle assembly (120), and that handle assembly (120) may eveninclude a battery or other on-board power source such that cable (114)is omitted. Still other suitable forms that generator (116) may take, aswell as various features and operabilities that generator (116) mayprovide, will be apparent to those of ordinary skill in the art in viewof the teachings herein.

As shown in FIG. 2, by way of example, one of the buttons (126) may beassociated with a “seal” mode, such that actuating the particular one ofthe buttons (126) only seals tissue, but does not cut tissue, when thetissue is being clamped between clamp arm (144) and blade (160). Inparticular, activation of a first one of the buttons (136) may causevibration of ultrasonic blade (160) at a relatively low amplitude.Similarly, by way of further example, the other of the buttons (126) maybe associated with a “cut and seal” mode such that actuating theparticular one of the buttons (126) may seal and cut tissue when thetissue is being clamped between clamp arm (44) and blade (160). Inparticular, activation of a second one of the buttons (136) may causevibration of ultrasonic blade (160) at a relatively high amplitude.Other suitable operational modes that may be associated with buttons(126) will be apparent to persons skilled in the art in view of theteachings herein.

III. Exemplary Alternative Surgical Instruments

While instruments such as instrument (110) are effective for cutting andsealing tissue as described above, some instances may call fordelivering varying amounts of energy or clamping forces to tissue inorder to optimize treatment of the tissue. For example, thicker ordenser tissue may require more energy to cut and/or seal than thinner orless dense tissue. Moreover, as tissue being treated changes from aninitial, unsealed state to a sealed state, the tissue thickness maydecrease, requiring less energy to cut and/or seal as the tissue becomesthinner. In addition to monitoring tissue characteristics, it may bedesirable to monitor thermal characteristics of the tissue due tofriction between the tissue and the blade (24, 160), in order to preventan undesired amount heat generation. Various examples of features thatmay be used to monitor tissue treatment and adjust outputs of instrument(20, 110) are described in greater detail below.

A. Instrument with Sensor to Detect Ultrasonic Blade Deflection

FIGS. 3-5 show an exemplary alternative instrument (210) that issubstantially similar to instrument (110) described above. Therefore,identical or similar structures are labeled with like reference numeralswithout further explanation below. It should therefore be understoodthat instrument (210) may be readily incorporated into system (10) as aform of instrument (20). Instrument (210) of this example includes ahandle assembly (220) that is just like handle assembly (120) describedabove. Handle assembly (220) is configured to receive an ultrasonictransducer (112). While not shown in FIG. 3, it should be understoodthat transducer (112) may be in communication with a generator (12, 116)via cable (14). A shaft assembly (230) extends distally from handleassembly (220). Shaft assembly (230) includes end effector (140) that isconfigured and operable substantially identically to end effector (140)described above. It should be understood, however, that shaft assembly(230) of this example is not limited to use with end effector (140). Byway of example only, shaft assembly (230) may instead be readilycombined with end effectors that are operable to apply electrosurgicalenergy to tissue, end effectors that are operable to apply staples totissue, end effectors that are operable to apply sutures to tissue, endeffectors that are operable to apply clips to tissue, etc.

Shaft assembly is (230) is similar to shaft assembly (130) such that itincludes an outer tube (232), an inner tube (233) defining a lumen(236), a waveguide (28) coaxially disposed within tubes (232, 233), anda distal seal member (234) sealing off proximal portions of lumen (236).Moreover, as shown best in FIG. 5, distal seal (234) includes a sensor(238) that is operably coupled to the distal seal (234). Because theinner aperture (240) of distal seal (234) is in touching contact withthe outer portion (e.g., outer diameter) of waveguide (28), vibrationsof waveguide (28) due to oscillation of waveguide (28) will beacoustically and mechanically transferred to distal seal (234) and,thus, sensor (238). In the present example, sensor (238) is embedded indistal seal (234). However, sensor (238) may be coupled to or incommunication with distal seal (234) in other suitable ways as will beapparent to persons skilled in the art in view of the teachings herein.In the example shown, sensor (238) is configured to detect levels oflateral deflection of ultrasonic blade (160), from which the sensor(238) may determine the pressure experienced by blade (160) whileinteracting with tissue.

In the present example, sensor (238) comprises an electroactivematerial. Various examples of suitable electroactive materials will beapparent to those of ordinary skill in the art in view of the teachingsherein. In other examples, sensor (238) may comprise other types ofsensors, such as a strain gauge, a piezoelectric sensor, a ferroelectricsensor, pressure sensitive layers of suitable materials such asgrapheme, and/or any other suitable kind(s) of sensors. Other suitableforms that sensor (238) may take will be apparent to persons skilled inthe art in view of the teachings herein. In the example shown, there isonly one sensor (238) of a single type. However, in other examples,there may be multiple sensors (238) of a single type; or multiplesensors (238) of multiple types.

Sensor (238) communicates the sensed deflection and/or pressure togenerator (12, 116) via wire (240) to contact ring (242), which is inelectrical communication with generator (12, 116). While contact ring(242) is shown to provide electrical communication between wire (240)and generator (12, 116), in other examples, there may be suitable otherstructures that provide electrical communication between line (240) andgenerator (12, 116). In some examples, wire (240) is omitted. In suchexamples, sensor (238) may communicate the sensed deflection and/orpressure to generator (12, 116) wirelessly using known components andmodalities. In some examples, the sensed deflection may be communicatedto a controller (not shown) that is located within instrument (210),which then converts the deflection data to a pressure level associatedwith the deflection data, which then communicates the pressure level tothe generator (12, 116).

Generator (12, 116) is configured to deliver a predetermined powerprofile to instrument (210) based on the pressure level communicated tothe generator (12, 116). By way of example, as the tissue is beingtreated, the tissue state changes from an initial unsealed state (e.g.,FIG. 4A) to a coagulated or partially sealed state (e.g., FIG. 4B), to asealed state (e.g., FIG. 4C), and the tissue thickness decreases throughthese transitions in tissue state. As the thickness of tissue beingclamped between clamp arm (144) and blade (160) decreases, the pressureexperienced by blade (160) from tissue decreases, resulting in adecreased deflection of blade (160). The value of the pressureexperienced by blade (160) may thus serve as an informational proxy forthe state of the tissue. Upon the signal of decreased pressure beingcommunicated to generator (12, 116), generator (12, 116), in someexamples, may decrease the power delivered to instrument (210). This mayreduce the delivery of ultrasonic power to the tissue by blade (160).

In some examples, changes in the delivered power level may be linearlycontinuous according to the sensed pressure level. That is, as thesensed pressure level increases or decreases, the level of powerdelivered to instrument (210) linearly increases or decreasescontinuously, respectively. Alternatively, the level of power deliveredto instrument (210) may be adjusted in a step-wise fashion.Particularly, as the sensed pressure level increases or decreasesbetween threshold pressure levels, the level of power delivered toinstrument (210) may increase or decrease, respectively, amongst variousdiscretely stepped levels of power. Moreover, in some examples,generator (12, 116) may cease providing power altogether if it receivesa signal indicative of a pressure level associated with tissue that isin a sealed, cut and sealed, or other state where it is desirable tocease provision of power. Such power levels and settings associated withparticular sensed pressure levels may be stored on a memory of generator(12, 116).

In the example shown, generator (12, 116) or instrument (210) maycommunicate to the operator the state of the tissue based on the sensedpressure level. For example, generator (12, 116) or instrument (210) mayprovide an indication to the operator that, based on the sensed pressurelevel, the tissue is in the initial state, a partially sealed state, asealed state, a cut and sealed state, or another tissue state that willbe apparent to persons skilled in the art in view of the teachingsherein. The indication to the operator may be visual, audio, physical(e.g., haptic), any other suitable indication modes, or combinationsthereof.

B. Surgical Instrument Including Pressure Sensor for Sensing Clamp Force

FIGS. 6-8 show an exemplary alternative instrument (310) that isconfigured to operate substantially similar to surgical instrument(110). Therefore, identical or similar structures are labeled with likereference numerals without further explanation below. It should beunderstood that instrument (310) may be readily incorporated into system(10) as a form of instrument (20). While an end effector is not shown inFIG. 6, instrument (310) includes an end effector that is just like endeffector (140) described above. As discussed in further detail below,instrument (310) is configured to sense different characteristicsassociated with clamping tissue being clamped by end effector (140); andis configured to deliver a particular amount of power to ultrasonicblade (160) based on the sensed characteristics.

As shown, instrument (310) includes a handle assembly (320) that is justlike handle assembly (120) described above. Particularly, handleassembly (320) includes pistol grip (128), trigger (124), and a seriesof links (322 a, 322 b) that are operably coupled to trigger (124).Links (322 a, 322 b) operably couple trigger (124) to clamp arm (144)such that clamp arm (144) will pivot in response to pivotal movement oftrigger (124) relative to pistol grip (128). Handle assembly (320) alsoincludes an actuating ring (324) that is coupled to link (322 b). Alinear driver (328) is coaxially positioned within actuating ring (324)and is operable to translate longitudinally relative to handle assembly(320). The distal end of linear driver (328) is pivotably coupled withclamp arm (144), such that longitudinal translation of linear driver(328) provides pivotal movement of clamp arm (144) toward and away fromblade (160). The proximal end of linear driver (328) includes anintegral, outwardly extending flange (327). In some versions, lineardriver (328) comprises an inner tube or an outer tube that forms part ofshaft assembly (130). A spring stack (326) is positioned betweenactuating ring (324) and flange (327). As will be described in greaterdetail below, spring stack (326) is operable to communicate longitudinaltranslation of actuating ring (324) to flange (327), and therebytranslate linear driver (328), up to a predetermined force threshold.

The distal end of link (322 a) is pivotably coupled to trigger (124) atpivot point (330), while the proximal end of link (322 a) is coupled tothe proximal end of link (322 b). Actuating ring (324) is secured to thedistal end of link (322 b). In the present example, a spring (329)biases link (322 b) in the distal direction, thereby biasing actuatingring (324) in the distal direction. In the present example, spring (329)comprises a coil tension spring, but in other examples may comprise anysuitable type of resilient member. It should be understood that, due tothe couplings between trigger (124), link (322 a, 322 b), actuating ring(324), and link system (328), actuation of trigger (124) with asufficient force to overcome the bias of spring (329) results inproximal translation of actuating ring (324). Similarly, releasing thesufficient force on trigger (124) causes actuating ring (324) to returnto the distal position in response to the resilient bias of spring(329).

As noted above, spring stack (326) is operable to communicatelongitudinal translation of actuating ring (324) to flange (327), andthereby translate linear driver (328), up to a predetermined forcethreshold, such that spring stack (326) acts as a force limiter withrespect to transmission of forces from actuating ring (324) to flange(327). In other words, spring stack (326) is configured to restrict theamount of clamping force that can be transferred to clamp arm (144) inresponse to pivotal movement of trigger (124) toward pistol grip (128).In the present example, spring stack (326) comprises a coaxially alignedstack of wave springs. However, in other examples, spring stack (326)may comprise any suitable type of resilient member(s) and arrangement.

In addition to overcoming the biasing force of spring (329) to pivotclamp arm (144) toward blade (160), clamp arm (144) also encountersresistance against closing or pivoting toward blade (160) from tissue,particularly during the clamping of tissue between clamp arm (144) andblade (160). Clamp arm (144) may thus provide some degree of mechanicalresistance to a clamping action as clamp arm (144) compresses tissueagainst blade (160). Spring stack (326) has sufficient rigidity to fullytransfer linear movement of actuating ring (324) to flange (327) whenclamp arm (144) provides mechanical resistance up to a certainpredetermined threshold. Spring stack (326) does not compress when themechanical resistance is below this threshold. However, when clamp arm(144) provides mechanical resistance beyond the threshold, spring stack(326) will begin to compress, such that further pivotal movement oftrigger (124) will result in further proximal movement of actuating ring(324) without resulting in further proximal movement of flange (324) orlinear driver (328). This compression of spring stack (326) may preventundue damage to components of instrument (310) and/or undue damage totissue that is being compressed by end effector (140). Various suitableforce thresholds that may be provided through spring stack (326) will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Instrument (310) of the present example further includes a plurality ofsensors (340, 342, 344, 346) that are configured to sense the clampingforce experienced by clamp arm (144) during the clamping of tissue. Inthe example shown, sensors (340, 342, 344, 346) are each pressuresensors, but in other examples, one or more of sensors may be othersuitable types of sensors which will be apparent to persons skilled inthe art in view of the teachings herein. As shown, there are foursensors (340, 342, 344, 346), but it will be understood that there maybe less than four sensors (340, 342, 344, 346), such as one, two, orthree sensors, or more than four sensors. For example, there may be onlyone sensor operably coupled to spring stack (326) (e.g., sensor (340)).

In the present example, sensor (340) is positioned on actuating ring(324) such that sensor (340) contacts a distal portion (348) of springstack (326). Sensor (342) is positioned on flange (327) such that sensor(342) contacts a proximal portion (350) of spring stack (326).Therefore, as actuating ring (324) is urged proximally in response toactuation of trigger (124), sensors (340, 342) experience the forcesand/or pressure from actuating ring (324) on spring stack (326), andbetween spring stack (326) and flange (327), respectively. Sensor (344)is positioned on proximal end of link (322 b), distally of spring (329),while sensor (346) is positioned distally of spring (329) and is coupledto the housing of handle assembly (320). Therefore, as link (322 b) ismoves proximally in response to trigger (124) being actuated, sensors(344, 346) are subjected to the forces from link (322 b) onto spring(329) and from the housing of handle assembly (320) onto spring (329).Other suitable configurations and positions of sensors (340, 342, 344,346) will be apparent to persons skilled in the art in view of theteachings herein.

Instrument (310) is configured to deliver an amount of energy towaveguide (28), and thus blade (160), based on the sensed clamping forceby one or more of sensors (340, 342, 344, 346). Particularly, in thepresent example, generator (12, 116) is configured to deliver apredetermined power profile to instrument (310) based on the pressurelevel communicated to generator (12, 116). When a lower pressure levelis sensed by one or more of sensors (340, 342, 344, 346), generator (12,116) delivers a “low” level of power, thereby causing blade (160) tovibrate at a relatively low level of ultrasonic power. Similarly, when ahigher pressure level is sensed by one or more of sensors (240, 242,244, 246), generator (12, 116) delivers a “high” level of power, therebycausing blade (160) to vibrate at a relatively high level of ultrasonicpower. Suitable amounts of power that are associated with the “high” andlow” levels will be apparent to persons skilled in the art in view ofthe teachings herein.

As discussed above, as the tissue is being treated, the tissue statechanges from an initial unsealed state (e.g., FIG. 4A) to a coagulatedor partially sealed state (e.g., FIG. 4B), to a sealed state (e.g., FIG.4C), and the tissue thickness decreases through these transitions. Asthe tissue thickness being clamped between clamp arm (144) and blade(160) decreases, the required clamping force on tissue decreases andthus the pressure level read by sensors (340, 342, 344, 346) maydecrease in some examples. Upon the signal of decreased pressure beingcommunicated to generator (12, 116), generator (12, 116) may decreasethe power delivered to instrument (310). In some examples, changes inthe delivered power level may be linearly continuous according to thesensed pressure level. That is, as the sensed pressure level increasesor decreases, the level of power delivered to instrument (310) linearlyincreases or decreases continuously, respectively. Alternatively, thelevel of power delivered to instrument (310) may be adjusted in astep-wise fashion. Particularly, as the sensed pressure level increasesor decreases between threshold pressure levels, the level of powerdelivered to instrument (310) may increase or decrease, respectively,amongst various discretely stepped levels of power. Moreover, in someexamples, generator (12, 116) may cease providing power altogether if itreceives a signal indicative of a pressure level associated with tissuethat is in a sealed, cut and sealed, or other state where it isdesirable to cease provision of power. Such power levels and settingsassociated with particular sensed pressure levels may be stored on amemory of generator (12, 116).

It will be understood that in addition to, or in lieu of, changing thepower output to alter the amount of energy delivered and (thus the heatgenerated due to friction), the clamp force of clamp arm (144) may beadjusted. This is because, as it will be understood by persons skilledin the art, heat generation due to friction is defined by the equationQ=μ×V×F, where μ is the kinetic coefficient of friction, V is therelative velocity between the surfaces, and F is the normal source.Thus, rather than decreasing or increasing V by decreasing or increasingthe power output to blade (160), respectively, the normal force (i.e.,the clamping force) may be decreased or increased. For example, as thetissue thickness decreases, it may be desirable to decrease the clampforce in order to decrease heat generation and, in some cases, toprevent cutting the tissue, such as in instances where only sealing isdesired. However, it may be desirable to do so without fully relying onthe skill of the operator or tactile, visual, or other feedback providedto the operator during an operation.

As shown in FIG. 7, instrument (310) includes a spring compressionmechanism (360) that is operably coupled to spring stack (326). In theexample shown, spring compression mechanism (360) is operable to adjustthe pre-load of spring stack (326). By adjusting the pre-load of springstack (326), spring compression mechanism (360) is operable to adjustthe mechanical resistance threshold provided by spring stack (326). Inother words, spring compression mechanism (360) is operable to adjustthe point at which spring stack (326) transitions from a fulltransmission state (i.e., where spring stack (326) provides fulltransmission of proximal movement of actuating ring (324) to flange(327)) to a non-transmission state (i.e., where spring stack (326)compresses in response to proximal movement of actuating ring (324),without transmitting proximal movement to flange (327)). This may inturn effectively decrease the clamping force of clamp arm (144)resulting from an actuation of trigger (124). Similarly, springcompression mechanism (360) is operable to increase the pre-load ofspring stack (326), thereby increasing the clamping force of clamp arm(144) resulting from an actuation of trigger (124). It will beunderstood that changing the pre-load of spring stack (326), trigger(124) may be actuated with the same sufficient force, but such actuationunder different levels of pre-loads results in different clamping forcesthat clamp arm (144) may provide.

In the present example, one of sensors (340, 342, 344, 346) may beconfigured to detect frequency slope. In other examples, instrument(310) may include an additional sensor or sensors that are configured todetect frequency slope during operation of instrument (310). In eithercontext, spring compression mechanism (360) may be configured toautomatically increase or decrease the pre-load on spring stack (326)based on the frequency slope detection of one of sensors (340, 342, 344,346). In addition or in the alternative, spring compression mechanism(360) may be configured to automatically increase or decrease thepre-load on spring stack (326) based on sensed pressure data from one ormore of sensors (340, 342, 344, 346). In addition or in the alternative,spring compression mechanism (360) may be operably coupled with othersensors, such as temperature sensors or other types of sensors (e.g.,positioned on shaft assembly (130) and/or end effector (140)), which mayfurther influence spring compression mechanism (360) automaticallyincreasing or decreasing the pre-load on spring stack (326).

In the example shown in FIG. 9, spring compression mechanism (360)comprises a solenoid (370) that is configured to adjust the pre-load ofspring stack (326) in response to data sensed by one of sensors (320,322, 324, 326). In such examples, solenoid (370) may be operable tocompress spring stack (326) among discrete levels of pre-load, and thuschange the clamping force of clamp arm (144) among discrete clamp forceamounts. Suitable configurations of solenoid (370) will be apparent topersons skilled in the art in view of the teachings herein. In otherexamples, the increasing or decreasing of clamping force based on theadjustment of solenoid may be linearly continuous.

In the example shown in FIG. 10, spring compression mechanism (360)comprises a torsional nut driven adjustment system (380) including a nut(382) threaded around a threaded rod (384). In such examples, nut (382)may be rotated in one direction to increase the pre-load; and in asecond, opposite direction to decrease the pre-load, in response to thesensed data. Other configurations of spring compression mechanism (360)that are suitable to increase and decrease the pre-load on spring stack(326) will be apparent to persons skilled in the art in view of theteachings herein. It should also be understood that spring compressionmechanism (360) may be used in addition to, or in lieu of, adjusting thepower output to blade (160) based on force data from sensors (320, 322,324, 326).

C. Instrument with User Adjustable Clamp Force

FIGS. 11-12 show an exemplary alternative instrument (410) that isconfigured to operate substantially similar to surgical instrument(110). Therefore, identical or similar structures are labeled with likereference numerals without further explanation below. It should beunderstood that instrument (410) may be readily incorporated into system(10) as a form of instrument (20). While an end effector is not shown inFIG. 11, instrument (410) includes an end effector that is just like endeffector (140) described above. Moreover, instrument (410) includes ahandle assembly (420) that is just like handle assembly (320) describedabove, except that in the example shown, certain elements, such assensors (340, 342, 344, 346), are omitted. However, it will beunderstood that such elements and their functionality may beincorporated into instrument (410) if desired.

Instrument (410) includes a toggle switch (460) that is operably coupledto spring stack (326) in order to change the pre-load of spring stack(326). That is, spring toggle switch (460) is operable to decrease thepre-load on spring stack (326), thus decreasing the effective clampingforce of clamp arm (144) resulting from actuation of trigger (124).Similarly, toggle switch (460) is operable to increase the pre-load onspring stack (326), thus increasing the effective clamping force ofclamp arm (144) resulting from actuation of trigger (124). Particularly,as shown, the operator may toggle the toggle switch (460) from a firstposition (adjacent to the “−” symbol) to a second position (adjacent tothe “+” symbol), or to positions between the first and second positions.

In the example shown, toggle switch (460) pivots about an axis betweenthe first and second positions, but in other examples may move axiallyor in other suitable manners. In the example shown, the first positionis associated with a “low” setting or clamp force while the secondposition is associated with a “high” setting or clamp force of clamp arm(144). Positions of toggle switch (460) between the first and secondpositions are associated with a setting between the “low” and “high”settings. Therefore, as the operator toggles the toggle switch (460)clockwise between the first and second positions, the pre-load of springstack (326) increases, while toggling switch (460) in a counterclockwisedirection results in the pre-load of spring stack (326) decreasing.Suitable amounts of clamp force associated with the “high,” “low” andother settings of clamp force will be apparent to persons skilled in theart in view of the teachings herein.

Thus, toggle switch (460) provides an operator with the ability toadjust the clamp force of end effector (140). In some examples, springstack (326) may move among discrete levels of pre-load in response totoggling of toggle switch (460), and thus change the clamping force ofclamp arm (144) among discrete clamp force amounts. However, in otherexamples, the increasing or decreasing of clamping force based on theadjustment of toggle switch (460) may be linearly continuous. Othersuitable configurations of toggle switch (460) will be apparent topersons skilled in the art in view of the teachings herein. Similarly,various suitable structures that may be coupled between toggle switch(460) and spring stack (326) in order to provide the adjustable pre-loadand clamping force will be apparent to those of ordinary skill in theart in view of the teachings herein.

In some examples, switch (460) may be used in conjunction with anadjustable amplitude switch that automatically or manually adjusts thepower delivered to blade (160) based on the position of toggle switch(460). The power may be adjusted manually or automatically (e.g., inresponse to input from sensors like sensors (340, 342, 344, 346)) orbased upon the position of toggle switch (460). In some examples, toggleswitch (460) may be selectively disengageable from shaft assembly (130)in order to enable rotation of components of shaft assembly (130).

IV. Exemplary Combinations

The following examples relate to various non-exhaustive ways in whichthe teachings herein may be combined or applied. It should be understoodthat the following examples are not intended to restrict the coverage ofany claims that may be presented at any time in this application or insubsequent filings of this application. No disclaimer is intended. Thefollowing examples are being provided for nothing more than merelyillustrative purposes. It is contemplated that the various teachingsherein may be arranged and applied in numerous other ways. It is alsocontemplated that some variations may omit certain features referred toin the below examples. Therefore, none of the aspects or featuresreferred to below should be deemed critical unless otherwise explicitlyindicated as such at a later date by the inventors or by a successor ininterest to the inventors. If any claims are presented in thisapplication or in subsequent filings related to this application thatinclude additional features beyond those referred to below, thoseadditional features shall not be presumed to have been added for anyreason relating to patentability.

Example 1

An ultrasonic instrument comprising: (a) a body; (b) a shaft assemblyextending distally from the body, wherein the shaft assembly comprisesan acoustic waveguide; (c) an end effector comprising an ultrasonicblade, wherein the ultrasonic blade is in acoustic communication withthe acoustic waveguide; and (e) a sensor configured to sense at leastone characteristic of the shaft assembly and/or the end effector,wherein the end effector is configured to be activated at varyingultrasonic power levels based on the at least one characteristic sensedby the sensor.

Example 2

The ultrasonic instrument of claim 1, wherein the shaft assemblycomprises a distal seal, wherein the acoustic waveguide is incommunication with the distal seal.

Example 3

The ultrasonic instrument of claim 2, wherein the sensor is positionedon the distal seal, wherein the sensor is configured to sense the forceson the distal seal in response to oscillation of the ultrasonicwaveguide.

Example 4

The ultrasonic waveguide of claim 3, wherein the sensor comprises anelectroactive material.

Example 5

The ultrasonic waveguide of claim 3, wherein the sensor comprises apiezoelectric component.

Example 6

The ultrasonic waveguide of claim 3, wherein the sensor comprises astrain gauge.

Example 7

The ultrasonic waveguide of claim 3, wherein the sensor comprises aferroelectric element.

Example 8

The ultrasonic waveguide of claim 1, wherein the sensor is positioned inthe body.

Example 9

The ultrasonic instrument of claim 1, wherein the end effector comprisesa clamp arm, wherein the clamp arm is pivotable toward and away from theultrasonic blade in order to clamp tissue between the clamp arm andultrasonic blade, wherein the at least one characteristic comprises aclamp force of the clamp arm onto tissue clamped between the clamp armand the ultrasonic blade.

Example 10

The ultrasonic instrument of claim 9, wherein the body comprises aspring element, wherein the spring element is configured to bias theclamp arm in the open position.

Example 11

The ultrasonic instrument of claim 10, wherein the sensor is positionedto contact the spring element.

Example 12

The ultrasonic instrument of claim 11, wherein the body furthercomprises a trigger, wherein the clamp arm is configured to pivot towardthe ultrasonic blade in response to actuation of the trigger, whereinthe spring element is configured to be compressed in response toactuation of the trigger.

Example 13

The ultrasonic instrument of claim 12, wherein the sensor is configuredto remain in contact with the spring element as the spring element iscompressed.

Example 14

The ultrasonic instrument of claim 11, wherein the sensor comprises apressure sensor.

Example 15

The ultrasonic instrument of claim 1, further comprising a generator,wherein the sensor is in communication with the generator, wherein thegenerator is configured to deliver power to the ultrasonic instrument inresponse to an input from the sensor.

Example 16

The ultrasonic instrument of claim 15, wherein the sensor is configuredto wirelessly transmit information to the generator.

Example 17

An ultrasonic instrument comprising: (a) a body; (b) a shaft assemblyextending distally from the body, wherein the shaft assembly comprisesan acoustic waveguide; (c) an end effector, comprising: (i) anultrasonic blade, wherein the ultrasonic blade is in acousticcommunication with the acoustic waveguide, and (ii) a clamp arm, whereinthe clamp arm is pivotable toward and away from the ultrasonic blade inorder to clamp tissue between the end effector and ultrasonic blade; and(d) a toggle switch, wherein the toggle switch is configured to adjust alevel of clamp force associated with the clamp arm upon movement of thetoggle switch.

Example 18

The ultrasonic instrument of claim 17, wherein the toggle switch ispositioned on the body.

Example 19

The ultrasonic instrument of claim 18, wherein the acoustic waveguide isconfigured to be activated at a predetermined power level based on theposition of the toggle switch.

Example 20

An ultrasonic instrument comprising: (a) a body; (b) a shaft assemblyextending distally from the body, wherein the shaft assembly comprisesan acoustic waveguide; (c) an end effector, comprising: (i) anultrasonic blade, wherein the ultrasonic blade is in acousticcommunication with the acoustic waveguide, and (ii) a clamp arm, whereinthe clamp arm is pivotable toward and away from the ultrasonic blade inorder to clamp tissue between the end effector and ultrasonic blade; and(d) a sensor, wherein the sensor is not positioned on the end effector,wherein the sensor is configured to sense a clamp force associated withthe clamp arm.

V. Miscellaneous

It should be understood that any of the versions of instrumentsdescribed herein may include various other features in addition to or inlieu of those described above. By way of example only, any of theinstruments described herein may also include one or more of the variousfeatures disclosed in any of the various references that areincorporated by reference herein. It should also be understood that theteachings herein may be readily applied to any of the instrumentsdescribed in any of the other references cited herein, such that theteachings herein may be readily combined with the teachings of any ofthe references cited herein in numerous ways. Other types of instrumentsinto which the teachings herein may be incorporated will be apparent tothose of ordinary skill in the art.

It should also be understood that any ranges of values referred toherein should be read to include the upper and lower boundaries of suchranges. For instance, a range expressed as ranging “betweenapproximately 1.0 inches and approximately 1.5 inches” should be read toinclude approximately 1.0 inches and approximately 1.5 inches, inaddition to including the values between those upper and lowerboundaries.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions of the devices described above may have application inconventional medical treatments and procedures conducted by a medicalprofessional, as well as application in robotic-assisted medicaltreatments and procedures. By way of example only, various teachingsherein may be readily incorporated into a robotic surgical system suchas the DAVINCI™ system by Intuitive Surgical, Inc., of Sunnyvale, Calif.Similarly, those of ordinary skill in the art will recognize thatvarious teachings herein may be readily combined with various teachingsof U.S. Pat. No. 6,783,524, entitled “Robotic Surgical Tool withUltrasound Cauterizing and Cutting Instrument,” published Aug. 31, 2004,the disclosure of which is incorporated by reference herein.

Versions described above may be designed to be disposed of after asingle use, or they can be designed to be used multiple times. Versionsmay, in either or both cases, be reconditioned for reuse after at leastone use. Reconditioning may include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, someversions of the device may be disassembled, and any number of theparticular pieces or parts of the device may be selectively replaced orremoved in any combination. Upon cleaning and/or replacement ofparticular parts, some versions of the device may be reassembled forsubsequent use either at a reconditioning facility, or by an operatorimmediately prior to a procedure. Those skilled in the art willappreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In one sterilization technique, thedevice is placed in a closed and sealed container, such as a plastic orTYVEK bag. The container and device may then be placed in a field ofradiation that can penetrate the container, such as gamma radiation,x-rays, or high-energy electrons. The radiation may kill bacteria on thedevice and in the container. The sterilized device may then be stored inthe sterile container for later use. A device may also be sterilizedusing any other technique known in the art, including but not limited tobeta or gamma radiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

1-20. (canceled)
 21. An ultrasonic surgical instrument, comprising: (a)a shaft assembly including an acoustic waveguide; (b) an end effectordistally extending from the shaft assembly, including: (i) an ultrasonicblade in acoustic communication with the acoustic waveguide, and (ii) aclamp arm movably secured relative to the ultrasonic blade andconfigured to move from an open position toward a closed position,wherein the clamp arm is further configured to compress tissue againstthe ultrasonic blade with a clamp force while moving the clamp armtoward the closed position; (c) a drive member operatively connected tothe clamp arm and configured to selectively actuate from a firstposition toward a second position to thereby respectively direct theclamp arm from the open position toward the closed position; and (d) aforce limiter operatively connected between the drive member and theclamp arm, wherein the force limiter is configured to transfer movementfrom the drive member toward the clamp arm and limit force transferredtherethrough to a first adjusted clamp force or a second adjusted clampforce for restricting the clamp force at the clamp arm respectivelyaccording to the first or second adjusted clamp force, wherein the forcelimiter is configured to be selectable between the first adjusted clampforce and the second adjusted clamp force by an operator.
 22. Theultrasonic surgical instrument of claim 21, wherein at least a portionof the force limiter is selectively movable from a first position to asecond position, wherein the at least the portion of the force limiterin the first position is configured to limit force to the first adjustedclamp force for restricting the clamp force at the clamp arm, andwherein the at least the portion of the force limiter in the secondposition is configured to limit force to the second adjusted clamp forcefor restricting the clamp force at the clamp arm.
 23. The ultrasonicsurgical instrument of claim 22, wherein the at least the portion of theforce limiter includes a switch, wherein the switch is selectivelymovable from the first position to the second position.
 24. Theultrasonic surgical instrument of claim 23, wherein the switch is atoggle switch configured to toggle between the first position and thesecond position.
 25. The ultrasonic surgical instrument of claim 24,wherein the force limiter further includes a resilient biasing feature,wherein the resilient biasing feature is operatively connected to theclamp arm such that the clamp arm is resiliently biasedly mountedrelative to the ultrasonic blade.
 26. The ultrasonic surgical instrumentof claim 21, further comprising a body, wherein the shaft assemblydistally extends from the body.
 27. The ultrasonic surgical instrumentof claim 26, wherein the shaft assembly is configured to selectivelyrotate relative to the body.
 28. The ultrasonic surgical instrument ofclaim 27, wherein at least a portion of the force limiter is selectivelymovable from a first engaged position to a disengaged position, whereinthe at least the portion of the force limiter is configured to inhibitrotation of the shaft assembly in the first engaged position, andwherein the at least the portion of the force limiter is configured toinhibit rotation of the shaft assembly in the disengaged position. 29.The ultrasonic surgical instrument of claim 28, wherein the at least theportion of the force limiter includes a switch, wherein the switch isselectively movable to the first engaged position, a second engagedposition, and the disengaged position, wherein the switch in the firstengaged position is configured to limit force to the first adjustedclamp force for restricting the clamp force at the clamp arm, andwherein the switch in the second engaged position is configured to limitforce to the second adjusted clamp force for restricting the clamp forceat the clamp arm.
 30. The ultrasonic surgical instrument of claim 29,wherein the switch is a toggle switch configured to toggle between thefirst engaged position, the second engaged position, and the disengagedposition.
 31. The ultrasonic surgical instrument of claim 21, whereinthe force limiter further includes: (i) a resilient biasing featureoperatively connected to the clamp arm such that the clamp arm isresiliently biasedly mounted relative to the ultrasonic blade with atleast one of a first pre-load or a second pre-load, and (ii) a switchselectively movable from a first position to a second position, whereinswitch in the first position directs the resilient biasing feature tothe first pre-load to thereby limit force to the first adjusted clampforce for restricting the clamp force at the clamp arm, and wherein theswitch in the second position directs the resilient biasing feature tothe second pre-load to thereby limit force to the second adjusted clampforce for restricting the clamp force at the clamp arm.
 32. Theultrasonic surgical instrument of claim 31, wherein the first pre-loadis a lower pre-load such that the first adjusted clamp force is a loweradjusted clamp force, and wherein the second pre-load is a higherpre-load such that the second adjusted clamp force is a higher adjustedclamp force.
 33. The ultrasonic surgical instrument of claim 32, whereinthe force limiter further includes an actuating member operativelyconnected to the drive member, wherein the resilient biasing feature ispositioned in compression between the actuating member and the switch,and wherein the drive member is configured to move toward the switch andfurther compress the resilient biasing feature as the drive member isselectively moved from the first position toward the second position.34. The ultrasonic surgical instrument of claim 33, wherein theresilient biasing feature includes a spring stack.
 35. The ultrasonicsurgical instrument of claim 21, wherein the drive member is configuredto pivot from the first position toward the second position.
 36. Theultrasonic surgical instrument of claim 21, wherein the drive member isa trigger.
 37. An ultrasonic surgical instrument, comprising: (a) abody; (b) a shaft assembly distally extending from the body andincluding an acoustic waveguide; (c) an end effector distally extendingfrom the shaft assembly, including: (i) an ultrasonic blade in acousticcommunication with the acoustic waveguide, and (ii) a clamp arm movablysecured relative to the ultrasonic blade and configured to move from anopen position toward a closed position, wherein the clamp arm is furtherconfigured to compress tissue against the ultrasonic blade with a clampforce while moving the clamp arm toward the closed position; (d) atrigger operatively connected to the clamp arm and configured toselectively actuate to thereby respectively direct the clamp arm fromthe open position toward the closed position; and (e) a spring stackoperatively connected between the trigger and the clamp arm, wherein thespring stack is configured to transfer movement from the trigger towardthe clamp arm and limit force transferred therethrough for restrictingthe clamp force at the clamp arm.
 38. A method of limiting a clamp forceof an ultrasonic surgical instrument, the ultrasonic surgical instrumentincluding (a) a shaft assembly including an acoustic waveguide; (b) anend effector distally extending from the shaft assembly, including: (i)an ultrasonic blade in acoustic communication with the acousticwaveguide, and (ii) a clamp arm movably secured relative to theultrasonic blade and configured to move from an open position toward aclosed position, wherein the clamp arm is further configured to compresstissue against the ultrasonic blade with the clamp force while movingthe clamp arm toward the closed position; (c) a drive member operativelyconnected to the clamp arm and configured to selectively actuate from afirst position toward a second position to thereby respectively directthe clamp arm from the open position toward the closed position; and (d)a force limiter operatively connected between the drive member and theclamp arm, wherein the force limiter is configured to transfer movementfrom the drive member toward the clamp arm and limit force transferredtherethrough to a first adjusted clamp force or a second adjusted clampforce for restricting the clamp force at the clamp arm respectivelyaccording to the first or second adjusted clamp force, wherein the forcelimiter is configured to be selectable between the first adjusted clampforce and the second adjusted clamp force by an operator, the methodcomprising: (a) selectively moving at least a portion of the forcelimiter to thereby adjust the clamp force from the first adjusted clampforce to the second adjusted clamp force and limit the clamp forceapplied via the clamp arm to the second adjusted clamp force.
 39. Themethod of claim 38, wherein the at least the portion of the forcelimiter includes a switch.
 40. The method of claim 39, wherein the forcelimiter further includes a resilient biasing feature, and wherein themethod further comprises selectively urging the drive member from thefirst position toward the second position to thereby compress theresilient biasing feature and move the clamp arm from the open positiontoward the closed position.